It was at Dane County Coliseum in Madison WI, Red Hot Chili Peppers with Foo Fighters opening. Late 90's if my memory is good, maybe the Californication tour.
My buddy and I ate at a high falutin' steak restaurant in Madison before the concert. Prime Rib, sauteed mushrooms, etc. Very rich stuff - the kind of food combination that can set my bowels on a path of destruction.
We hit the concert, and before FF got started, things had began boiling and I knew I had to find a restroom quick. I find a restroom and stall, and having no time at all to make sure the restroom was properly stocked (it WAS a public event...you gotta scout these things out beforehand), I assume the position. The toilet paper dispenser was one of those slide to the second roll things, and the open roll was empty, so I do the slide...that one is empty also.
The explosion occurs. I know then, gotta pull up the pants, find some paper towels, and hope that wet creeks poopie hadn't destroyed my underwear. I leave the stall...no paper towels anywhere, and the other open stall...TP is empty there too.
So, I had to then cruise the food stands looking for paper towels and finally finding some, I inconspicuously grab a fistful and head back to the restroom. Fortunately the damage was "slight"...but still - Total Concert Buzzkill.
I made a vow then and there, any public event I go to the rest of my life, I'm not eating anything that could possibly cause anything close to a repeat performance.